System and method for intersection collision prevention

ABSTRACT

Provided are a system and method for intersection collision prevention. The intersection collision prevention system may include a collision determination unit configured to calculate a first space between a preceding vehicle running in the same direction as a host vehicle and at least one of a yellow center line and an oncoming vehicle located in the opposite lane with respect to the host vehicle and compare the first space to a predetermined second space to determine a danger of a collision; and a control unit configured to adjust a collision danger warning time point according to a determination result of the collision determination unit.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2017-0026543, filed on Feb. 28, 2017, the disclosureof which is incorporated herein by reference in its entirety.

BACKGROUND 1. Field

Exemplary embodiments relates to a vehicle system, and moreparticularly, to a system and method for intersection collisionprevention.

2. Discussion of Related Art

Generally, a vehicle operating system may refer to a system related tooperation of a vehicle (e.g., running of a vehicle, etc.) and mayinclude a collision prevention system.

Such a collision prevention system may refer to a system for preventingcollision between a host vehicle and other vehicles. Particularly, inrecent years, there is a need to study a Cross Traffic Assistance (CTA)system among such collision prevention systems.

SUMMARY

Exemplary embodiments may provide an intersection collision preventionsystem and method capable of giving a warning about a danger of acollision with a vehicle running in the opposite direction, that is, anoncoming vehicle located in the opposite lane and performing brakingcontrol when a host vehicle enters and passes through an intersection.

Also, exemplary embodiments may provide an intersection collisionprevention system and method capable of giving a warning about a dangerof a collision with a preceding vehicle running in the same directionand performing braking control when a host vehicle enters and passesthrough an intersection.

According to an aspect of exemplary embodiments, there is provided anintersection collision prevention system including a collisiondetermination unit configured to calculate a first space between apreceding vehicle running in the same direction as a host vehicle and atleast one of a yellow center line and an oncoming vehicle located in theopposite lane with respect to the host vehicle and compare the firstspace to a predetermined second space to determine a danger of acollision; and a control unit configured to adjust a collision dangerwarning time point according to a determination result of the collisiondetermination unit.

According to another aspect of exemplary embodiments, there is providedan intersection collision prevention method including calculating afirst space between a preceding vehicle running in the same direction asa host vehicle and at least one of a yellow center line and an oncomingvehicle located in the opposite lane with respect to the host vehicle;comparing the first space to a predetermined second space to determine adanger of a collision; and adjusting a collision danger warning timepoint according to a collision danger determination result.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentdisclosure will become more apparent to those of ordinary skill in theart by describing exemplary embodiments thereof in detail with referenceto the accompanying drawings, in which:

FIG. 1 is a block diagram illustrating an intersection collisionprevention system according to exemplary embodiments;

FIG. 2 illustrates a method of determining a danger of a collision whena host vehicle is entering and passing through an intersection by meansof an intersection collision prevention system according to exemplaryembodiments;

FIG. 3 illustrates a method of calculating a first space through anintersection collision prevention system according to exemplaryembodiments;

FIG. 4 illustrates a method of calculating a first space by setting avirtual route of a host vehicle through an intersection collisionprevention system according to exemplary embodiments;

FIG. 5 is a flowchart illustrating an intersection collision preventionmethod according to exemplary embodiments;

FIG. 6 is a flowchart illustrating a method of acquiring image data andradar sensing data according to exemplary embodiments;

FIGS. 7 to 10 are flowcharts illustrating a method of calculating afirst space according to exemplary embodiments;

FIG. 11 is a flowchart illustrating a method of adjusting a collisiondanger warning time point on the basis of a collision dangerdetermination result according to exemplary embodiments;

FIG. 12 is a flowchart illustrating a method of adjusting a brakingforce on the basis of a collision danger determination result accordingto exemplary embodiments; and

FIG. 13 is a flowchart illustrating a method of adjusting a steeringforce on the basis of a collision danger determination result accordingto exemplary embodiments.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, exemplary embodiments will be described in detail withreference to the accompanying drawings so that they can be easilypracticed by those skilled in the art. The exemplary embodiments may,however, be embodied in many different forms and should not be construedas being limited to the embodiments set forth herein.

To clearly describe exemplary embodiments, portions irrelevant to thedescription are omitted, and the same or similar elements are denoted bythe same reference numerals.

Throughout the specification, when one part is referred to as being“connected” to another part, it should be understood that the former canbe “directly connected” to the latter or “electrically connected” to thelatter via an intervening part. Furthermore, when a part is referred toas “including” elements, it should be understood that it can includeonly those elements, or other elements as well as those elements unlessspecifically described otherwise.

It will be understood that when one part is referred to as being “on”another part, it can be directly on another part or intervening partsmay be present therebetween. In contrast, when a part is referred to asbeing “directly on” another part, there are no intervening partstherebetween.

It will be understood that, although the terms first, second, third,etc. may be used herein to describe various parts, components, regions,layers and/or sections, but are not limited thereto. These terms areonly used to distinguish one part, component, region, layer, or sectionfrom another part, component, region, layer or section. Thus, a firstpart, component, region, layer, or section discussed below could betermed a second part, component, region, layer, or section withoutdeparting from the scope of the embodiments.

The technical terms used herein are to simply mention a particularexemplary embodiment and are not meant to limit the exemplaryembodiments. An expression used in the singular encompasses theexpression of the plural, unless it has a clearly different meaning inthe context. In the specification, it is to be understood that the termssuch as “including” or “having” etc., are intended to indicate theexistence of specific features, regions, integers, steps, operations,elements, and/or components, and are not intended to preclude thepossibility that one or more other specific features, regions, integers,steps, operations, elements, components, or combinations thereof mayexist or may be added.

Spatially relative terms, such as “below,” “above,” and the like, may beused herein for ease of description to describe one part's relationshipto another part(s) as illustrated in the figures. It will be understoodthat the spatially relative terms are intended to encompass differentmeanings or operations of a device in use in addition to the meaningsdepicted in the drawings. For example, if the device in the figures isturned over, parts described as “below” other parts would then beoriented “above” the other parts. Thus, the exemplary term “below” canencompass both an orientation of above and below. Devices may beotherwise rotated 90 degrees or by other angles and the spatiallyrelative descriptors used herein are interpreted accordingly.

Unless otherwise defined, all terms used herein, including technical orscientific terms, have the same meanings as those generally understoodby those with ordinary knowledge in the field of art to which thepresent invention belongs. Such terms as those defined in a generallyused dictionary are to be interpreted to have the meanings equal to thecontextual meanings in the relevant field of art, and are not to beinterpreted to have idealized or excessively formal meanings unlessclearly defined in the present application.

Hereinafter, exemplary embodiments will be described in detail withreference to the accompanying drawings so that they can be easilypracticed by those skilled in the art. The exemplary embodiments may,however, be embodied in many different forms and should not be construedas being limited to the embodiments set forth herein.

FIG. 1 is a block diagram illustrating an intersection collisionprevention system according to exemplary embodiments.

Referring to FIG. 1, an intersection collision prevention system 100according to exemplary embodiments may include a camera sensor 110, aradar sensor 120, a collision determination unit 130, a control unit140, a danger warning device 150, a braking control device 160, and asteering control device 170.

The camera sensor 110 may include at least one of a lens, a lens holder,an image sensor, an image processor, and a camera microcontroller unit(MCU), and the image processor receives image data from the imagesensor. To this end, the image processor and the image sensor may beconnected to each other through a connector. The camera MCU may receiveimage data processed by the image processor and may transmit thereceived image data to the collision determination unit 130. Here, thecamera sensor 110 may include a mono camera, a stereo camera, or asurround vision camera and may capture at least one of areas around ahost vehicle, that is, areas in front of, behind, and to the left/rightof the host vehicle to generate image data.

The radar sensor 120 may include at least one of a radar module and aradar MCU. Here, the radar module and the radar MCU may be connected toeach other and configured to transmit and receive data. The radar sensor120 may be a sensor device that uses electromagnetic waves to measuredistance, speed, and angle of an object. The radar sensor 120 may detectobjects within a horizontal angle range of 30 degrees and a distance ofup to 150 meters ahead by using at least one of Frequency ModulatedCarrier Wave (FMCW) and Pulse Carrier. The radar MCU may control otherdevices (e.g., a radar processor for processing a radar sensing output)of the host vehicle connected to the radar module. The control mayinclude at least one of, for example, power supply control, resetcontrol, clock (CLK) control, data communication control, and memorycontrol. Representatively, the radar sensor 120 may use 77 GHz frequencyband or other suitable bands to sense at least one of areas around thehost vehicle, that is, areas in front of, behind, and to the left/rightof the host vehicle and to generate radar sensing data on the basis ofthe sensed result. The radar sensing data of the radar sensor 120 may betransmitted to the collision determination unit 130. Meanwhile, theradar processor may process the radar sensing data output by the radarsensor 120, and the processing may include enlarging an object sensedahead or focusing on an area of an object among the overall viewingarea.

FIG. 2 illustrates a method of determining a danger of a collision whena host vehicle is entering and passing through an intersection by meansof an intersection collision prevention system according to exemplaryembodiments.

Referring to FIGS. 1 and 2, the collision determination unit 130according to exemplary embodiments may determine a danger of a collisionbetween a host vehicle 10 and a preceding vehicle 20 in the same runningdirection. For example, when the host vehicle 10 enters and passesthrough an intersection, the collision determination unit 130 maydetermine a danger of a collision between the host vehicle 10 and thepreceding vehicle 20 running in the same direction as that of the hostvehicle 10.

Also, the collision determination unit 130 may determine a danger of acollision between the host vehicle 10 and vehicles in the oppositedirection (including a running vehicle and a stationary vehicle), thatis, an oncoming vehicle 30 located in the opposite lane with respect tothe host vehicle 10. For example, when the host vehicle 10 enters andpasses through an intersection, the collision determination unit 130 maydetermine a danger of a collision between the host vehicle 10 and thevehicles in the opposite direction (including a running vehicle and astationary vehicle), that is, the oncoming vehicle 30 located in theopposite lane with respect to the host vehicle 10.

Here, the collision determination unit 130 may determine whether thehost vehicle 10 enters an intersection by using information receivedfrom the camera sensor 110 (a lane disconnection, a “go straight”/“turnleft” indication, or the like). That is, the collision determinationunit 130 may receive image data from the camera sensor 110 and mayrecognize at least one of a lane disconnection and a “go straight”/“turnleft” indication from the image data received from the camera sensor 110to determine whether the host vehicle enters an intersection.

While the host vehicle 10 enters and passes through an intersection, acollision may occur when the preceding vehicle 20 running in the samedirection as the host vehicle 10 and a vehicle running in the oppositedirection, that is, the oncoming vehicle 30 located in the opposite lanewith respect to the host vehicle 10 have a small space therebetween. Inorder to prevent such a danger of a collision, the collisiondetermination unit 130 may calculate a first space A between thepreceding vehicle 20 running in the same direction as the host vehicle10 and the vehicle running in the opposite direction, that is, theoncoming vehicle 30 located in the opposite lane with respect to thehost vehicle 10. Here, the collision determination unit 130 detects ayellow center line to detect the oncoming vehicle 30 located in theopposite lane with respect to the host vehicle 10.

The collision determination unit 130 may calculate a first space Abetween the yellow center line and the preceding vehicle 20 running inthe same direction as the host vehicle 10.

That is, the collision determination unit 130 may calculate a firstspace A between the preceding vehicle 20 running in the same directionas the host vehicle 10 and at least one of the yellow center line andthe oncoming vehicle 30 located in the opposite lane with respect to thehost vehicle 10.

FIG. 3 illustrates a method of calculating a first space through anintersection collision prevention system according to exemplaryembodiments.

Referring to FIGS. 1 to 3, the intersection collision prevention systemaccording to exemplary embodiments may calculate a first space A betweenthe preceding vehicle 20 running in the same direction as the hostvehicle 10 and at least one of the yellow center line and the oncomingvehicle 30 located in the opposite lane with respect to the host vehicle10 by means of the collision determination unit 130 and may compare thefirst space A to a predetermined second space to determine a danger of acollision. Also, the intersection collision prevention system accordingto exemplary embodiments may compare the first space to thepredetermined second space to determine a danger of a collision by meansof the collision determination unit 130. Also, the intersectioncollision prevention system according to exemplary embodiments mayadjust a collision danger warning time point according to adetermination result of the collision determination unit 130 by means ofthe control unit 140.

As described above, when the host vehicle 10 enters and passes throughan intersection, the intersection collision prevention system accordingto exemplary embodiments calculates a spatial width in a direction inwhich the host vehicle 10 will travel to determine whether the hostvehicle 10 can pass. When the host vehicle 10 cannot pass, theintersection collision prevention system according to exemplaryembodiments gives a warning and controls the vehicle to prevent acollision.

The intersection collision prevention system according to exemplaryembodiments will be described below in detail.

Referring to FIGS. 1 to 3 again, the collision determination unit 130may calculate a first space A between the preceding vehicle 20 runningin the same direction as the host vehicle 10 and the vehicle running inthe opposite direction, that is, the oncoming vehicle 30 located in theopposite lane with respect to the host vehicle 10 and may compare thefirst space A to a reference value (a second space) to determine adanger of a collision. Here, the reference value may be used tocalculate a warning time point from a TTC map based on speed of the hostvehicle 10.

That is, the collision determination unit 130 may calculate a firstspace A between the preceding vehicle 20 running in the same directionas the host vehicle 10 and the vehicle running in the oppositedirection, that is, the oncoming vehicle 30 located in the opposite lanewith respect to the host vehicle 10 on the basis of at least one ofimage data received from the camera sensor 110 and radar sensing datareceived from the radar sensor 120 and may compare the first space A tothe reference value (the second space) to determine the danger of acollision.

In particular, the collision determination unit 130 may determine thedanger of a collision by using at least one of a width of the hostvehicle 10, a center position in the host vehicle 10, a current locationof the host vehicle 10, a width of the oncoming vehicle 30, a centerposition in the oncoming vehicle 30, a current location of the oncomingvehicle 30, a width of the preceding vehicle 20, a center position inthe preceding vehicle 20, and a current location of the precedingvehicle 20. As an example, the collision determination unit 130 maycalculate a first space A by using a distance from a predeterminedposition in the host vehicle 10 to one side of the oncoming vehicle 30and a distance from a predetermined position in the host vehicle 10 toone side of the preceding vehicle 20. Here, the one side of the oncomingvehicle 30 and the one side of the preceding vehicle 20 may be leftsides with respect to their respective running directions. However, theexemplary embodiments are not limited thereto, and the one side of theoncoming vehicle 30 and the one side of the preceding vehicle 20 may besides adjacent to the host vehicle 10 with respect to their respectiverunning directions. Here, the predetermined position in the host vehicle10 may be the center position in the host vehicle 10. However, theexemplary embodiments are not limited thereto, and the predeterminedposition may include any position in the host vehicle 10.

As another example, the collision determination unit 130 may calculate afirst space A by using the width of the host vehicle 10, the centerposition in the host vehicle 10, the width of the oncoming vehicle 30,the center position in the oncoming vehicle 30, the width of thepreceding vehicle 20, and the center position in the preceding vehicle20.

That is, the collision determination unit 130 may calculate a firstdistance B1 between the center of the width of the host vehicle 10 andthe center of the width of the preceding vehicle 20 on the basis of atleast one of image data received from the camera sensor 110 and radarsensing data received from the radar sensor 120.

Also, the collision determination unit 130 may calculate a seconddistance B2 between the center of the width of the host vehicle 10 andthe center of the width of the vehicle running in the oppositedirection, that is, the center of the width of the oncoming vehicle 30located in the opposite lane with respect to the host vehicle 10 on thebasis of at least one of image data received from the camera sensor 110and radar sensing data received from the radar sensor 120.

Also, the collision determination unit 130 may calculate a thirddistance B3, which is the width of the preceding vehicle 20, on thebasis of at least one of image data received from the camera sensor 110and radar sensing data received from the radar sensor 120.

Also, the collision determination unit 130 may calculate a fourthdistance B4, which is the width of the vehicle running in the oppositedirection, that is, the oncoming vehicle 30 located in the opposite lanewith respect to the host vehicle 10 on the basis of at least one ofimage data received from the camera sensor 110 and radar sensing datareceived from the radar sensor 120.

Subsequently, the collision deteimination unit 130 may calculate a firstspace A between the preceding vehicle 20 running in the same directionas the host vehicle 10 and the vehicle running in the oppositedirection, that is, the oncoming vehicle 30 located in the opposite lanewith respect to the host vehicle 10, by using Equation 1 below:

A=(B1−B3/2)+(B2−B4/2).   [Equation 1]

As shown in Equation 1, the collision determination unit 130 maycalculate a first value by dividing a third width B3 by two and thensubtracting the quotient from a first width B1. Also, the collisiondetermination unit 130 may calculate a second value by dividing a fourthwidth B4 by two and then subtracting the quotient from a second widthB2. Subsequently, the collision determination unit 130 may calculate afirst space A between the preceding vehicle 20 running in the samedirection as the host vehicle 10 and the vehicle running in the oppositedirection, that is, the oncoming vehicle 30 located in the opposite lanewith respect to the host vehicle 10, by adding the first value and thesecond value.

Also, the collision determination unit 130 may compare the first space Ato a reference value (a second space) to determine a danger of acollision.

For example, the collision determination unit 130 may compare the firstspace A to the reference value (the second space) and may determine thatthere is a danger of a collision when the first space A is less than thereference value (the second space). On the other hand, the collisiondetermination unit 130 may compare the first space A to the referencevalue (the second space) and may determine that there is no danger of acollision when the first space A is greater than or equal to thereference value (the second space).

When the first space A is greater than the width of the host vehicle 10,the host vehicle 10 can pass with no collision. However, when the hostvehicle 10 is actually running, the first space A may need to be muchgreater than the width of the host vehicle 10. Accordingly, thereference value may be set to a value greater than the width of the hostvehicle 10, and the reference value (the second space) may be set to avalue obtained by adding a certain margin a to the width of the hostvehicle 10. In this case, the certain margin a may be set to a value of10 cm to 100 cm. However, the exemplary embodiments are not limitedthereto, and the certain margin a may be modified and set.

Still referring to FIGS. 1 to 3, the collision determination unit 130may calculate a first space A between the yellow center line and thepreceding vehicle 20 running in the same direction as the host vehicle10 and may compare the first space A to a reference value (a secondspace) to determine a danger of a collision. Here, the reference valuemay be used to calculate a warning time point from a TTC map based onspeed of the host vehicle 10.

That is, the collision determination unit 130 may calculate a firstspace A between the yellow center line and the preceding vehicle 20running in the same direction as the host vehicle 10 on the basis of atleast one of image data received from the camera sensor 110 and radarsensing data received from the radar sensor 120 and may compare thefirst space A to the reference value (the second space) to determine adanger of a collision.

In particular, the collision determination unit 130 may determine thedanger of a collision by using at least one of the width of the hostvehicle 10, the center position in the host vehicle 10, the currentlocation of the host vehicle 10, the yellow center line, the width ofthe preceding vehicle 20, the center position in the preceding vehicle20, and the current location of the preceding vehicle 20.

As an example, the collision determination unit 130 may calculate afirst space A by using a distance from a predetermined position in thehost vehicle 10 to the yellow center line and a distance from apredetermined position in the host vehicle 10 to one side of thepreceding vehicle 20. Here, the one side of the preceding vehicle 20 maybe a left side with respect to its running direction, as shown in FIGS.1 to 3. However, the exemplary embodiments are not limited thereto, andthe one side of the preceding vehicle 20 may be a side adjacent to thehost vehicle 10 with respect to its running direction. Here, thepredetermined position in the host vehicle 10 may be the center positionin the host vehicle 10. However, the exemplary embodiments are notlimited thereto, and the predetermined position may include any positionin the host vehicle 10.

As another example, the collision determination unit 130 may calculate afirst space A by using the width of the host vehicle 10, the centerposition in the host vehicle 10, the yellow center line, the width ofthe preceding vehicle 20, and the center position in the precedingvehicle 20.

That is, the collision determination unit 130 may calculate a firstdistance between the center of the width of the host vehicle 10 and thecenter of the width of the preceding vehicle 20 on the basis of at leastone of image data received from the camera sensor 110 and radar sensingdata received from the radar sensor 120.

Also, the collision determination unit 130 may calculate a seconddistance between the yellow center line and the center of the width ofthe host vehicle 10 on the basis of at least one of image data receivedfrom the camera sensor 110 and radar sensing data received from theradar sensor 120.

Also, the collision determination unit 130 may calculate a thirddistance, which is the width of the preceding vehicle 20, on the basisof at least one of image data received from the camera sensor 110 andradar sensing data received from the radar sensor 120.

Then, the collision determination unit 130 may calculate a first spaceby dividing the third distance by two, subtracting the quotient from thefirst distance, and adding the second distance to the difference.

Also, the collision determination unit 130 may compare the first spaceto a reference value (a second space) to determine a danger of acollision.

For example, the collision determination unit 130 may compare the firstspace to the reference value (the second space) and may determine thatthere is a danger of a collision when the first space is less than thereference value (the second space). On the other hand, the collisiondetermination unit 130 may compare the first space to the referencevalue (the second space) and may determine that there is no danger of acollision when the first space is greater than or equal to the referencevalue (the second space).

When the first space is greater than the width of the host vehicle 10,the host vehicle 10 can pass with no collision. However, when the hostvehicle 10 is actually running, the first space may need to be muchgreater than the width of the host vehicle 10. Accordingly, thereference value may be set to a value greater than the width of the hostvehicle 10, and the reference value (the second space) may be set to avalue obtained by adding a certain margin a to the width of the hostvehicle 10. In this case, the certain margin a may be set to a value of10 cm to 100 cm. However, the exemplary embodiments are not limitedthereto, and the certain margin a may be modified and set.

After determining a danger of a collision, the collision determinationunit 130 may generate collision determination data and may provide thegenerated collision determination data to the control unit 140.

The collision determination unit 130 may receive image data from thecamera sensor 110 and may recognize at least one of a lane disconnectionand a “go straight”/“turn left” indication from the image data receivedfrom the camera sensor 110 to determine whether the host vehicle 10enters an intersection.

Also, when it is determined that the host vehicle 10 enters theintersection, the collision determination unit 130 may calculate a firstspace through the above-described method and determine a danger of acollision on the basis of the calculated first space.

Also, when it is determined that the host vehicle 10 does not enter theintersection, the collision determination unit 130 may determine adanger of a collision through predetermined collision preventioncontrol. Here, the predetermined collision prevention control may belongitudinal collision prevention control. However, the exemplaryembodiments are not limited thereto, and the predetermined collisionprevention control may be intersection collision prevention control.

Still referring to FIGS. 1 to 3, the control unit 140 may controloperation of at least one of the danger warning device 150, the brakingcontrol device 160, and the steering control device 170 on the basis ofthe provided collision determination data.

For example, the control unit 140 may control operation of the dangerwarning device 150.

In detail, when the collision determination unit 130 determines thatthere is a danger of a collision, the control unit 140 may control thedanger warning device 150 so that the collision danger warning timepoint is put earlier than to a reference value. That is, when thecollision determination unit 130 determines that there is a danger of acollision because a route along which the host vehicle 10 will pass hasa small width, the control unit 140 may control the danger warningdevice 150 so that the collision danger warning time point is putearlier than the reference value. Here, the warning time point may becalculated from a TTC map based on speed of the host vehicle 10.

On the other hand, when the collision determination unit 130 determinesthat there is little or no danger of a collision, the control unit 140may control the danger warning device 150 so that the collision dangerwarning time point is maintained at the reference value. That is, whenthe collision determination unit 130 determines that there is little orno danger of a collision because a route along which the host vehicle 10will pass has a large width, the control unit 140 may control the dangerwarning device 150 so that the collision danger warning time point ismaintained at a default value.

The danger warning device 150 may display the danger of a collision onthe basis of a control signal input from the control unit 140. In thiscase, the collision danger warning time point may be put earlier thanthe default value when it is determined that there is a danger of acollision, and the collision danger warning time point may be maintainedat the default value when it is determined that there is little or nodanger of a collision.

The danger warning device 150 may generate a warning signal in at leastone of an audio type, a video type, and a haptic type in order to warn adriver of a specific danger situation. For example, in order to output awarning sound, the danger warning device 150 may use a car sound systemto output the warning sound. Alternatively, in order to display awarning message, the danger warning device 150 may output the warningmessage through a HUD display or a side mirror display. Alternatively,in order to generate a warning vibration, the danger warning device 150may operate a vibration motor mounted on a steering wheel.

For example, the control unit 140 may control operation of the brakingcontrol device 160.

In detail, when the collision determination unit 130 determines thatthere is a danger of a collision, the control unit 140 may control thebraking control device 160 so that the host vehicle 10 is decelerated.

As an example, when it is determined that there is a danger of acollision because a route along which the host vehicle 10 will pass hasa small width, the control unit 140 may control the braking controldevice 160 so that the host vehicle 10 is decelerated. In this case, inorder to avoid the collision, a deceleration rate should be large, andthus the control unit 140 may control the braking control device 160 sothat the deceleration rate is greater than an average deceleration rate.Here, the average deceleration rate may be calculated on the basis ofthe widths of two vehicles or the distance between the yellow centerline and the preceding vehicle, and the deceleration may be performedaccording to the average deceleration rate. As another example, theaverage deceleration rate refers to an average braking force needed toavoid a collision, and the average deceleration rate may be calculatedon the basis of an average value between a minimum braking rate and amaximum braking rate that are needed to avoid a collision.

As another example, when it is determined that there is a danger of acollision because a route along which the host vehicle 10 will pass hasa small width, the control unit 140 may control the braking controldevice 160 so that the host vehicle 10 is decelerated. In this case, inorder to avoid the collision, a deceleration rate should be large, andthus the control unit 140 may control the braking control device 160 sothat the deceleration rate is maximized.

On the other hand, when the collision determination unit 130 determinesthat there is little or no danger of a collision, the control unit 140may control the braking control device 160 so that the speed of the hostvehicle 10 is maintained at a reference value. That is, when it isdetermined that there is little or no danger of a collision because aroute along which the host vehicle 10 will pass has a large width, thecontrol unit 140 may control the braking control device 160 so that thespeed of the host vehicle 10 is maintained at the reference value. Inthis case, the danger of a collision is low, and thus the control unit140 may control the braking control device 160 so that the decelerationrate is smaller than or equal to the average deceleration rate.

The braking control device 160 may control operation of a car brake andmay also control pressure of the brake. For example, when a forwardcollision is probable, the braking control device 160 may performcontrol so that an emergency brake is automatically operated on thebasis of a control signal of the control unit 140, irrespective ofwhether a driver has operated a brake.

For example, the control unit 140 may control operation of the steeringcontrol device 170.

Even when a route along which the host vehicle 10 will pass has a largewidth, the danger of a collision may increase if the host vehicle 10 isleaned toward one side. Accordingly, in order to reduce the danger of acollision, the control unit 140 may control the steering control device170 so that the host vehicle 10 passes through the center of first spaceA between the preceding vehicle 20 running in the same direction as thehost vehicle 10 and the vehicle running in the opposite direction, thatis, the oncoming vehicle 30 located in the opposite lane with respect tothe host vehicle 10. That is, when the collision determination unit 130determines that the first space is greater than the second space, thecontrol unit 140 may control the steering control device 170 so that thehost vehicle 10 passes through the center of the first space.

The steering control device 170 may control a motor-driven powersteering (MDPS) system for operating a steering wheel. For example, whena car collision is probable, the steering control device 170 may controlsteering of a car to a direction in which the collision can be avoided.

When the host vehicle 10 enters and passes through an intersection, theintersection collision prevention system 100 according to exemplaryembodiments may give a warning about a danger of a collision with thevehicle running in the opposite direction, that is, the oncoming vehicle30 located in the opposite lane with respect to the host vehicle 10 andthen may perform braking control. Also, when the host vehicle 10 entersand passes through an intersection, the intersection collisionprevention system 100 according to exemplary embodiments may give awarning about a danger of a collision with the preceding vehicle 20running in the same direction as the host vehicle 10 and then mayperform braking control.

When a danger of a collision between the host vehicle 10 and thepreceding vehicle 20 running in the same direction as the host vehicle10 is predicted, the intersection collision prevention system 100according to exemplary embodiments does not calculate the first valueand the second value on the basis of Equation 1. The intersectioncollision prevention system 100 according to exemplary embodiments maydetect a danger of a collision, perform steering control, and operateautonomous emergency braking (AEB) when the distance between the hostvehicle 10 and the preceding vehicle 20 running in the same direction asthe host vehicle 10 is smaller than or equal to a certain value. Also,when a danger of a collision between the host vehicle 10 and the vehiclerunning in the opposite direction, that is, the oncoming vehicle 30located in the opposite lane with respect to the host vehicle 10 ispredicted, the intersection collision prevention system 100 according toexemplary embodiments does not calculate the first value and the secondvalue on the basis of Equation 1. The intersection collision preventionsystem 100 according to exemplary embodiments may detect a danger of acollision, perform steering control, and operate AEB when a vehicle bodyof the host vehicle 10 at least partially overlaps a vehicle body of thevehicle running in the opposite direction, that is, the oncoming vehicle30 located in the opposite lane with respect to the host vehicle 10.

Whether the host vehicle 10 enters an intersection is not necessary whenthe intersection collision prevention system 100 according to exemplaryembodiments gives a warning about a danger of a collision between thehost vehicle 10 and the preceding vehicle 20 and performs brakingcontrol. A situation in which the host vehicle 10 enters an intersectionhas been described as an example. Here, whether the host vehicle 10enters an intersection may be determined by using GPS signals or roadmap information of a navigation device disposed in the host vehicle 10.The collision prediction method that has been described with referenceto FIG. 3 may be applied to predict a danger of a collision between thehost vehicle 10 and the vehicle running in the opposite direction, thatis, the oncoming vehicle 30 located in the opposite lane with respect tothe host vehicle 10 as well as a danger of a collision between the hostvehicle 10 and the preceding vehicle 20.

FIG. 4 illustrates a method of calculating a first space by setting avirtual route of a host vehicle through an intersection collisionprevention system according to exemplary embodiments.

Referring to FIG. 4, the collision determination unit 130 according toexemplary embodiments may virtually generate a predicted route of thehost vehicle on the basis of a lane in which the host vehicle is to runafter passing through the intersection and may calculate a first spaceon the basis of a space between the predicted route and at least one ofthe oncoming vehicle and the yellow center line and a space between thepredicted route and the preceding vehicle.

For example, as shown in FIG. 4, the host vehicle 10 may be located in aleft turn lane. In this case, the collision determination unit 130according to exemplary embodiments may recognize at least one of a lanedisconnection and a “go straight”/“turn left” indication from image datato determine whether the host vehicle 10 enters an intersection.

When it is determined that the host vehicle 10 enters an intersection,the collision determination unit 130 may virtually generate a predictedroute 1 of the host vehicle 10 on the basis of a lane in which the hostvehicle 10 is running (or a current location of the host vehicle 10) anda lane in which the host vehicle 10 is to run after passing through theintersection.

For example, the collision determination unit 130 may virtually generatea predicted route 1 of the host vehicle 10 on the basis of the centerposition in the host vehicle 10 and the center position in the lane inwhich the host vehicle 10 is to run after passing through theintersection. Also, the collision determination unit 130 may generate avirtual lane on the basis of lanes in which the host vehicle 10 isrunning and a lane in which the host vehicle is to run after passingthrough the intersection and may virtually generate a predicted route 1of the host vehicle 10 on the basis of the generated virtual lane.

In particular, the collision determination unit 130 may virtuallygenerate the predicted route 1 of the host vehicle 10 in real time,periodically, or at at least one arbitrary time point.

The collision determination unit 130 may calculate a space (a) betweenthe predicted route 1 and the oncoming vehicle 30. The collisiondetermination unit 130 may calculate a space (b) between the predictedroute 1 and the preceding vehicle 20.

The collision determination unit 130 may calculate a space (a) betweenthe predicted route 1 and the yellow center line. The collisiondetermination unit 130 may calculate a space (b) between the predictedroute 1 and the preceding vehicle 20.

In particular, the collision determination unit 130 may calculate aspace between the predicted route 1 and the oncoming vehicle 30, a spacebetween the predicted route 1 and the preceding vehicle 20, a spacebetween the predicted route 1 and the yellow center line, and the likein real time, periodically, or at at least one arbitrary time point.

The collision determination unit 130 may calculate a first space on thebasis of the space (a) between the predicted route 1 and the oncomingvehicle 30 and the space (b) between the predicted route 1 and thepreceding vehicle 20. The collision determination unit 130 may calculatea first space on the basis of the space (a) between the predicted route1 and the yellow center line and the space (b) between the predictedroute 1 and the preceding vehicle 20.

Here, the method of calculating a first space will not be described indetail for the sake of brevity because the first space calculationmethod that has been described with reference to FIGS. 2 and 3 may beapplied as it is.

The collision determination unit 130 may compare the first space to apredetermined second space to determine a danger of a collision. Here,the method of determining a danger of a collision will not be describedin detail for the sake of brevity because the collision dangerdetermination method that has been described with reference to FIGS. 2and 3 may be applied as it is.

The control unit 140 may control operation of at least one of the dangerwarning device 150, the braking control device 160, and the steeringcontrol device 170 on the basis of the determination result of thecollision determination unit 130. . Here, the control of operation ofthe danger warning device 150, the braking control device 160, and thesteering control device 170 will not be described in detail for the sakeof brevity because the control of operation of the danger warning device150, the braking control device 160, and the steering control device 170that has been described with reference to FIGS. 2 and 3 may be appliedas it is.

In addition, when it is determined that the host vehicle 10 does notenter an intersection, the collision determination unit 130 may performpredetermined collision prevention control. Here, the predeterminedcollision prevention control may be longitudinal collision preventioncontrol. However, the exemplary embodiments are not limited thereto, andthe predetermined collision prevention control may be intersectioncollision prevention control.

The method of setting a virtual route of a host vehicle, calculating aspace between a preceding vehicle and at least one of an oncomingvehicle and a yellow center line, and determining a danger of acollision to prevent the collision through the intersection collisionprevention system according to exemplary embodiments may be applied whenthe host vehicle turns left, as shown in the drawings. However, theexemplary embodiments are not limited thereto, and the method may alsobe applied when the host vehicle goes straight and when the host vehicleturns right.

An intersection collision prevention method according to exemplaryembodiments will be described below with reference to the accompanyingdrawings (FIGS. 5 to 13). Particularly, the parts associated with theintersection collision prevention system according to exemplaryembodiments which have been described above will no longer be describedbelow for the sake of brevity.

The intersection collision prevention method according to exemplaryembodiments may be performed by means of the intersection collisionprevention system 100 according to exemplary embodiments including acamera sensor 110, a radar sensor 120, a collision determination unit130, a control unit 140, a danger warning device 150, a braking controldevice 160, a steering control device 170, and the like.

FIG. 5 is a flowchart illustrating an intersection collision preventionmethod according to exemplary embodiments.

Referring to FIG. 5, the intersection collision prevention methodaccording to exemplary embodiments may include calculating a first space(S100), determining a danger of a collision (S200), and adjusting acollision danger warning time point (S300).

First, a first space between a preceding vehicle running in the samedirection as a host vehicle and at least one of a yellow center line andan oncoming vehicle located in the opposite lane with respect to thehost vehicle may be calculated (S100).

Subsequently, a danger of a collision may be determined by comparing thefirst space calculated in step S100 to a predetermined second space(S200).

Subsequently, a collision danger warning time point may be adjustedaccording to a result of determining the danger of a collision in stepS200 (S300).

FIG. 6 is a flowchart illustrating a method of acquiring image data andradar sensing data according to exemplary embodiments.

Referring to FIG. 6, the intersection collision prevention methodaccording to exemplary embodiments may further include at least one ofacquiring image data (S11) and acquiring radar sensing data (S12) beforethe calculation of a first space (S100).

In the acquisition of image data (S11), areas around the host vehiclemay be captured to generate the image data. For example, first, theareas around the host vehicle may be captured through a camera sensor(S11-1). Subsequently, the image data may be generated on the basis ofinformation regarding the areas around the host vehicle captured in stepS11-1 (S11-2).

In the acquisition of radar sensing data (S12), areas around the hostvehicle may be sensed to generate the radar sensing data. For example,first, the areas around the host vehicle may be sensed through a radarsensor (S12-1). Subsequently, the radar sensing data may be generated onthe basis of information regarding the areas around the host vehiclesensed in step S12-1 (S12-2).

Referring to FIG. 5 again, in step S100, a first space between apreceding vehicle and at least one of a yellow center line and anoncoming vehicle may be calculated on the basis of at least one of theimage data and the radar sensing data.

Subsequently, in step S200, a danger of a collision may be determined bycomparing the first space calculated in step S100 to a predeterminedsecond space.

Subsequently, in step S300, a collision danger warning time point may beadjusted according to a result of determining the danger of a collisionin step S200.

FIGS. 7 to 10 are flowcharts illustrating a method of calculating afirst space according to exemplary embodiments.

Referring to FIG. 7, the method of calculating a first space accordingto exemplary embodiments may include calculating a first space between apreceding vehicle running in the same direction as a host vehicle and anoncoming vehicle located in the opposite lane with respect to the hostvehicle.

That is, in step S112, the first space between the preceding vehiclerunning in the same direction as the host vehicle and the vehiclerunning in the opposite direction, that is, the oncoming vehicle locatedin the opposite lane with respect to the host vehicle may be calculatedon the basis of at least one of the image data received in step S11 andthe radar sensing data received in step S12.

In particular, in step S112, the first space may be calculated by usingat least one of the width of the host vehicle, the center position inthe host vehicle, the current location of the host vehicle, the width ofthe oncoming vehicle, the center position in the oncoming vehicle, thecurrent location of the oncoming vehicle, the width of the precedingvehicle, the center position in the preceding vehicle, and the currentlocation of the preceding vehicle.

As an example, in step S112, the first space may be calculated by usinga distance from a predetermined position in the host vehicle to one sideof the oncoming vehicle and a distance from a predetermined position inthe host vehicle to one side of the preceding vehicle. Here, the oneside of the oncoming vehicle and the one side of the preceding vehiclemay be left sides with respect to their running directions, as shown inthe drawings. However, the exemplary embodiments are not limitedthereto, and the one side of the oncoming vehicle and the one side ofthe preceding vehicle may be sides adjacent to the host vehicle withrespect to their running directions. Here, the predetermined position inthe host vehicle may be the center position in the host vehicle.However, the exemplary embodiments are not limited thereto, and thepredetermined position may include any position in the host vehicle.

As another example, in step S112, the first space may be calculated byusing the width of the host vehicle, the center position in the hostvehicle, the width of the oncoming vehicle, the center position in theoncoming vehicle, the width of the preceding vehicle, and the centerposition in the preceding vehicle.

That is, in step S112, first, a first distance between the center of thewidth of the host vehicle and the center of the width of the precedingvehicle may be calculated on the basis of at least one of the image datareceived in step S11 and the radar sensing data received in step S12.

Subsequently, a second distance between the center of the width of thehost vehicle and the center of the width of a vehicle running in theopposite direction, that is, the oncoming vehicle located in theopposite lane with respect to the host vehicle may be calculated on thebasis of at least one of the image data received in step S11 and theradar sensing data received in step S12.

Subsequently, a third distance, which is the width of the precedingvehicle, may be calculated on the basis of at least one of the imagedata received in step S11 and the radar sensing data received in stepS12.

Subsequently, a fourth distance, which is the width of the vehiclerunning in the opposite direction, that is, the oncoming vehicle locatedin the opposite lane with respect to the host vehicle may be calculatedon the basis of at least one of the image data received in step S11 andthe radar sensing data received in step S12.

Subsequently, the first space between the preceding vehicle running inthe same direction as the host vehicle and the vehicle running in theopposite direction, that is, the oncoming vehicle located in theopposite lane with respect to the host vehicle may be calculated usingEquation 1 below:

A=(B1−B3/2)+(B2−B4/2)   [Equation 1]

As shown in Equation 1, a first value may be calculated by dividing athird width B3 by two and then subtracting the quotient from a firstwidth B1. Also, a second value may be calculated by dividing a fourthwidth B4 by two and then subtracting the quotient from a second widthB2. Subsequently, a first space A between the preceding vehicle 20running in the same direction as the host vehicle 10 and the vehiclerunning in the opposite direction, that is, the oncoming vehicle 30located in the opposite lane with respect to the host vehicle 10 may becalculated by adding the first value and the second value.

The method of calculating a first space according to exemplaryembodiments may further include determining whether the host vehicleenters an intersection (S111) before step S112.

For example, in step S111, at least one of a lane disconnection and a“go straight”/“turn left” indication may be recognized from the imagedata to determine whether the host vehicle enters an intersection.

Step S112 or step S113 may be performed depending on the determinationresult of step S111.

That is, when the determination result of step S111 is that the hostvehicle enters the intersection, the first space may be calculatedthrough step S112. Also, when the determination result of step Sill isthat the host vehicle does not enter the intersection, predeterminedcollision prevention control may be performed through step S123. Here,the predetermined collision prevention control may be longitudinalcollision prevention control. However, the exemplary embodiments are notlimited thereto, and the predetermined collision prevention control maybe intersection collision prevention control.

Referring to FIG. 8, the method of calculating a first space accordingto exemplary embodiments may include calculating a first space betweenthe yellow center line and the preceding vehicle running in the samedirection as the host vehicle (S122).

That is, in step S122, the first space between the yellow center lineand the preceding vehicle running in the same direction as the hostvehicle may be calculated on the basis of at least one of the image datareceived in step S11 and the radar sensing data received in step S12.

In particular, in step S122, the first space may be calculated by usingat least one of the width of the host vehicle, the center position inthe host vehicle, the current location of the host vehicle, the yellowcenter line, the width of the preceding vehicle, the center position inthe preceding vehicle, and the current location of the precedingvehicle.

As an example, in step S122, the first space may be calculated by usinga distance from a predetermined position in the host vehicle to theyellow center line and a distance from a predetermined position in thehost vehicle to one side of the preceding vehicle. Here, the one side ofthe preceding vehicle may be a left side with respect to its runningdirection, as shown in the drawings. However, the exemplary embodimentsare not limited thereto, and the one side of the preceding vehicle maybe a side adjacent to the host vehicle with respect to its runningdirection. Here, the predetermined position in the host vehicle may bethe center position in the host vehicle. However, the exemplaryembodiments are not limited thereto, and the predetermined position mayinclude any position in the host vehicle.

As another example, in step S122, the first space may be calculated byusing the width of the host vehicle, the center position in the hostvehicle, the yellow center line, the width of the preceding vehicle, andthe center position in the preceding vehicle.

That is, in step S122, a first distance between the center of the widthof the host vehicle and the center of the width of the preceding vehiclemay be calculated on the basis of at least one of the image datareceived in step S11 and the radar sensing data received in step S12.

Subsequently, a second distance between the center of the width of thehost vehicle and the yellow center line may be calculated on the basisof at least one of the image data received in step Sll and the radarsensing data received in step S12.

Subsequently, a third distance, which is the width of the precedingvehicle, may be calculated on the basis of at least one of the imagedata received in step S11 and the radar sensing data received in stepS12.

Subsequently, the first space may be calculated by dividing the thirddistance by two, subtracting the quotient from the first distance, andadding the second distance to the difference.

The method of calculating a first space according to exemplaryembodiments may further include determining whether the host vehicleenters an intersection (S121) before step S122.

For example, in step S121, at least one of a lane disconnection and a“go straight”/“turn left” indication may be recognized from the imagedata to determine whether the host vehicle enters an intersection.

Step S122 or step S123 may be performed depending on the determinationresult of step S121.

That is, when the determination result of step S121 is that the hostvehicle enters the intersection, the first space may be calculatedthrough step S122. Also, when the determination result of step S121 isthat the host vehicle does not enter the intersection, predeterminedcollision prevention control may be performed through step S123. Here,the predetermined collision prevention control may be longitudinalcollision prevention control. However, the exemplary embodiments are notlimited thereto, and the predetermined collision prevention control maybe intersection collision prevention control.

Referring to FIG. 9, first, the method of calculating a first spaceaccording to exemplary embodiments may include virtually generating apredicted route of the host vehicle on the basis of a lane in which thehost vehicle is to run (S132).

That is, in step S132, the predicted route of the host vehicle may bevirtually generated on the basis of a lane in which the host vehicle iscurrently running (or the current location of the host vehicle) and alane in which the host vehicle is to run after passing through theintersection.

For example, in step S132, the predicted route of the host vehicle maybe virtually generated on the basis of the center position in the hostvehicle and the center position in the lane in which the host vehicle isto run after passing through the intersection. Also, in step S132, avirtual lane may be generated on the basis of lanes in which the hostvehicle is running and a lane in which the host vehicle is to run afterpassing through the intersection, and a predicted route of the hostvehicle may be virtually generated on the basis of the generated virtuallane.

In particular, in step S132, the predicted route of the host vehicle maybe virtually generated in real time, periodically, or at at least onearbitrary time point.

Subsequently, the first space may be calculated on the basis of thespace between the oncoming vehicle and the predicted route generated instep S132 and the space between the preceding vehicle and the predictedroute generated in step S132 (S133).

For example, first, the space between the predicted route and theoncoming vehicle may be calculated. Subsequently, the space between thepredicted route and the preceding vehicle may be calculated. Inparticular, the space between the predicted route and the oncomingvehicle, the space between the predicted route and the precedingvehicle, and the like may be calculated in real time, periodically, orat at least one arbitrary time point. Subsequently, the first space maybe calculated on the basis of the space between the predicted route andthe oncoming vehicle and the space between the predicted route and thepreceding vehicle.

Also, step S133 will not be described in detail for the sake of brevitybecause the first space calculation method of step S112 that has beendescribed with reference to FIG. 7 may be applied as it is.

The method of calculating a first space according to exemplaryembodiments may further include determining whether the host vehicleenters an intersection (S131) before step S132.

For example, in step S131, at least one of a lane disconnection and a“go straight”/“turn left” indication may be recognized from the imagedata to determine whether the host vehicle enters an intersection.

Step S132 and step S133, or step S134, may be performed depending on thedetermination result of step S131.

That is, when the determination result of step S131 is that the hostvehicle enters the intersection, the predicted route of the host vehiclemay be virtually generated through step S132, and the first space may becalculated through step S133. Also, when the determination result ofstep S131 is that the host vehicle does not enter the intersection,predetermined collision prevention control may be performed through stepS134. Here, the predetermined collision prevention control may belongitudinal collision prevention control. However, the exemplaryembodiments are not limited thereto, and the predetermined collisionprevention control may be intersection collision prevention control.

Referring to FIG. 10, first, the method of calculating a first spaceaccording to exemplary embodiments may include virtually generating apredicted route of the host vehicle on the basis of a lane in which thehost vehicle is to run (S142).

That is, in step S142, the predicted route of the host vehicle may bevirtually generated on the basis of a lane in which the host vehicle iscurrently running (or the current location of the host vehicle) and alane in which the host vehicle is to run after passing through theintersection.

For example, in step S142, the predicted route of the host vehicle maybe virtually generated on the basis of the center position in the hostvehicle and the center position in the lane in which the host vehicle isto run after passing through the intersection. Also, in step S142, avirtual lane may be generated on the basis of lanes in which the hostvehicle is running and a lane in which the host vehicle is to run afterpassing through the intersection, and a predicted route of the hostvehicle may be virtually generated on the basis of the generated virtuallane.

In particular, in step S142, the predicted route of the host vehicle maybe virtually generated in real time, periodically, or at at least onearbitrary time point.

Subsequently, the first space may be calculated on the basis of thespace between the yellow center line and the predicted route generatedin step S142 and the space between the preceding vehicle and thepredicted route generated in step S142 (S143).

For example, first, the space between the predicted route and the yellowcenter line may be calculated. Subsequently, the space between thepredicted route and the preceding vehicle may be calculated. Inparticular, the space between the predicted route and the yellow centerline, the space between the predicted route and the preceding vehicle,and the like may be calculated in real time, periodically, or at atleast one arbitrary time point. Subsequently, the first space may becalculated on the basis of the space between the predicted route and theyellow center line and the space between the predicted route and thepreceding vehicle.

Also, step S143 will not be described in detail for the sake of brevitybecause the first space calculation method of step S122 that has beendescribed with reference to FIG. 8 may be applied as it is.

The method of calculating a first space according to exemplaryembodiments may further include determining whether the host vehicleenters an intersection (S141) before step S142.

For example, in step S141, at least one of a lane disconnection and a“go straight”/“turn left” indication may be recognized from the imagedata to determine whether the host vehicle enters an intersection.

Step S142 and step S143, or step S144, may be performed depending on thedetermination result of step S141.

That is, when the determination result of step S141 is that the hostvehicle enters the intersection, the predicted route of the host vehiclemay be virtually generated through step S142, and the first space may becalculated through step S143. Also, when the determination result ofstep S141 is that the host vehicle does not enter the intersection,predetermined collision prevention control may be performed through stepS144. Here, the predetermined collision prevention control may belongitudinal collision prevention control. However, the exemplaryembodiments are not limited thereto, and the predetermined collisionprevention control may be intersection collision prevention control.

The intersection collision prevention method according to exemplaryembodiments may control at least one of a collision danger warning timepoint, a braking force, and a steering force on the basis of a collisiondanger determination result. The control of the collision danger warningtime point, the braking force, and the steering force according to thecollision danger determination result will be described below withreference to the accompanying drawings.

FIG. 11 is a flowchart illustrating a method of adjusting a collisiondanger warning time point on the basis of a collision dangerdetermination result according to exemplary embodiments.

FIG. 12 is a flowchart illustrating a method of adjusting a brakingforce on the basis of a collision danger determination result accordingto exemplary embodiments.

FIG. 13 is a flowchart illustrating a method of adjusting a steeringforce on the basis of a collision danger determination result accordingto exemplary embodiments.

Referring to FIGS. 11 to 13, first, a danger of a collision of a hostvehicle may be determined (S210). That is, in step S210, the danger of acollision may be determined by comparing the first space calculated instep S100 to a reference value (a second space).

For example, in step S210, it may be determined that there is a dangerof a collision when the first space is compared to the reference value(the second space) and is less than the reference value (the secondspace). On the other hand, in step S210, it may be determined that thereis no danger of a collision when the first space is compared to thereference value (the second space) and is greater than or equal to thereference value (the second space).

When the first space is greater than the width of the host vehicle, thehost vehicle can pass with no collision. However, when the host vehicleis actually running, the first space may need to be much greater thanthe width of the host vehicle. Accordingly, the reference value may beset to a value greater than the width of the host vehicle, and thereference value (the second space) may be set to a value obtained byadding a certain margin a to the width of the host vehicle. In thiscase, the certain margin a may be set to a value of 10 cm to 100 cm.However, the exemplary embodiments are not limited thereto, and thecertain margin a may be modified and set.

Referring to FIG. 11, the method of adjusting a collision danger warningtime point according to exemplary embodiments may include adjusting thecollision danger warning time point according to the collision dangerdetermination result of step S210 (S300).

Subsequently, when the collision danger determination result of stepS210 is that there is a danger of a collision, a warning about thedanger of a collision may be given to put the collision danger warningtime point earlier than a reference value (S310).

For example, when the collision danger determination result of step S210is that there is a danger of a collision, a danger warning device may becontrolled to put the collision danger warning time point earlier than areference value. That is, when there is a danger of a collision becausea route along which the host vehicle will pass has a small width, thedanger warning device may be controlled to put the collision dangerwarning time point earlier than a default value. Here, the warning timepoint may be calculated from a TTC map based on speed of the hostvehicle.

When the collision danger determination result of step S210 is thatthere is less or no danger of a collision, a warning about the danger ofa collision may be controlled to maintain the collision danger warningtime point at the reference value (S320).

For example, when the collision danger determination result of step S210is that there is little or no danger of a collision, the danger warningdevice may be controlled to maintain the collision danger warning timepoint at the reference value. That is, when it is determined that thereis little or no danger of a collision because a route along which thehost vehicle will pass has a large width, the danger warning device maybe controlled to maintain the collision danger warning time point at thedefault value.

The collision danger warning according to exemplary embodiments may beprovided through at least one of a signal output, a display output, anda haptic output.

That is, the danger warning device may generate a warning signal in atleast one of an audio type, a video type, and a haptic type in order towarn a driver of a specific danger situation. For example, in order tooutput a warning sound, the danger warning device may use a car soundsystem to output the warning sound. Alternatively, in order to display awarning message, the danger warning device may output the warningmessage through a HUD display or a side mirror display. Alternatively,in order to generate a warning vibration, the danger warning device mayoperate a vibration motor mounted on a steering wheel.

Referring to FIG. 12, the method of adjusting a braking force accordingto exemplary embodiments may include adjusting the braking forceaccording to the collision danger determination result of step S210(S400).

When the collision danger determination result of step S210 is thatthere is a danger of a collision, the braking force may be generated sothat the host vehicle is decelerated relative to a reference value(S410).

For example, when the collision danger determination result of step S210is that there is a danger of a collision because a route along which thehost vehicle will pass has a small width, the braking control device maybe controlled to decelerate the host vehicle. In this case, in order toavoid the collision, a deceleration rate should be large, and thus thebraking control device may be controlled so that the deceleration rateis greater than an average deceleration rate. Here, the averagedeceleration rate may be calculated on the basis of the widths of twovehicles or the distance between the yellow center line and thepreceding vehicle, and the deceleration may be performed according tothe average deceleration rate. As another example, the averagedeceleration rate refers to an average braking force needed to avoid acollision, and the average deceleration rate may be calculated on thebasis of an average value between a minimum braking rate and a maximumbraking rate that are needed to avoid a collision.

As another example, when the collision danger determination result ofstep S210 is that there is a danger of a collision because a route alongwhich the host vehicle will pass has a small width, the braking controldevice may be controlled to decelerate the host vehicle. In this case,in order to avoid the collision, a deceleration rate should be large,and thus the braking control device may be controlled to maximize thedeceleration rate.

When the collision danger determination result of step S210 is thatthere is less or no danger of a collision, the braking force may becontrolled to maintain the speed of the host vehicle at a referencevalue (S420).

For example, when the collision danger determination result of step S210is that there is little or no danger of a collision, the braking controldevice may be controlled to maintain the speed of the host vehicle atthe reference value. That is, when the collision danger determinationresult of step S210 is that there is little or no danger of a collisionbecause a route along which the host vehicle will pass has a largewidth, the braking control device may be controlled to maintain thespeed of the host vehicle at the reference value. In this case, thedanger of a collision is low, and thus the braking control device may becontrolled so that the deceleration rate is smaller than or equal to theaverage deceleration rate.

Here, the braking control device may control operation of a car brakeand may also control pressure of the brake. For example, when a forwardcollision is probable, the braking control device may perform control sothat an emergency brake is automatically operated on the basis of acontrol signal, irrespective of whether a driver has operated a brake.

Referring to FIG. 13, the method of adjusting a steering force accordingto exemplary embodiments may include adjusting the steering forceaccording to the collision danger determination result of step S210(S500).

When the collision danger determination result of step S210 is thatthere is a danger of a collision, the steering force may be generated sothat the host vehicle is steered to avoid the collision (S510).

For example, when the collision danger determination result of step S210is that there is a danger of a collision, the steering control devicemay be controlled so that the host vehicle is steered to avoid thecollision.

Here, the steering control device may control a motor-driven powersteering (MDPS) system for operating a steering wheel. For example, whena car collision is probable, the steering control device may controlsteering of a car to a direction in which the collision can be avoided.

When the collision danger determination result of step S210 is thatthere is less or no danger of a collision, the steering force may becontrolled to maintain the steering of the host vehicle at a referencevalue (S520).

For example, when the collision danger determination result of step S210is that there is less or no danger of a collision, the steering controldevice may be controlled to maintain the steering of the host vehicle atthe reference value.

Even when a route along which the host vehicle will pass has a largewidth, the danger of a collision may increase if the host vehicle isleaned toward one side. Accordingly, in order to reduce the danger of acollision, the steering control device may be controlled so that thehost vehicle passes through the center of the first space between thepreceding vehicle running in the same direction as the host vehicle andthe vehicle running in the opposite direction, that is, the oncomingvehicle located in the opposite lane with respect to the host vehicle.That is, when the collision danger determination result of step S210 isthat the first space is greater than the second space, the steeringcontrol device may be controlled so that the host vehicle passes throughthe center of the first space.

The intersection collision prevention method according to exemplaryembodiments may include giving a warning about a danger of a collisionwith the vehicle running in the opposite direction, that is, theoncoming vehicle 30 located in the opposite lane with respect to thehost vehicle 10 and performing braking control when the host vehicle 10enters and passes through an intersection. Also, the intersectioncollision prevention method according to exemplary embodiments mayinclude giving a warning about a danger of a collision with thepreceding vehicle 20 running in the same direction as the host vehicle10 and performing braking control when the host vehicle 10 enters andpasses through an intersection.

According to the intersection collision prevention system and methodaccording exemplary embodiments, it is possible to give a warning abouta danger of a collision with a vehicle running in the oppositedirection, that is, an oncoming vehicle located in the opposite lane andperform braking control when a host vehicle enters and passes through anintersection.

According to the intersection collision prevention system and methodaccording exemplary embodiments, it is also possible to give a warningabout a danger of a collision with a preceding vehicle running in thesame direction and perform braking control when a host vehicle entersand passes through an intersection.

In one or more exemplary embodiments, the functions described may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions can be stored on ortransmitted as one or more instructions or code on a computer-readablemedium. Computer-readable media include all of communication media andcomputer storage media including any medium for facilitating transfer ofa computer program from one place to another place. Storage media may beany available media that can be accessed by a computer. By way ofexample, and not limitation, such computer-readable media can include aRAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic diskstorage or other magnetic storage devices, or any other medium that canbe used to carry or store desired program code in the form ofinstructions or data structures and that can be accessed by a computer.Also, any connection is properly termed a computer-readable medium. Forexample, if the software is transmitted from a website, server, or otherremote source using a coaxial cable, fiber optic cable, twisted pair,digital subscriber line (DSL), or wireless technologies such asinfrared, radio, and microwave, then the coaxial cable, fiber opticcable, twisted pair, DSL, or wireless technologies such as infrared,radio, and microwave are included in the definition of medium. Disk anddisc, as used herein, includes compact disc (CD), laser disc, opticaldisc, digital versatile disc (DVD), floppy disk and Blu-ray disc wheredisks usually reproduce data magnetically, while discs reproduce dataoptically with lasers. Combinations of the above should also be includedwithin the scope of computer-readable media.

When exemplary embodiments are implemented by program code or codesegments, each code segment may represent a procedure, a function, asubprogram, a program, a routine, a subroutine, a module, a softwarepackage, a class, or any combination of instructions, data structures,or program statements. A code segment may be coupled to another codesegment or a hardware circuit by passing and/or receiving information,data, arguments, parameters, or memory contents.

Information, arguments, parameters, data, etc. may be passed, forwarded,or transmitted via any suitable means including memory sharing, messagepassing, token passing, network transmission, etc. Additionally, in someaspects, the steps and/or operations of a method or algorithm may resideas one or any combination or set of codes and/or instructions on amachine-readable medium and/or computer-readable medium, which may beincorporated into a computer program product.

For a software implementation, the techniques described herein may beimplemented with modules (e.g., procedures, functions, and so on) thatperform the functions described herein. Software codes may be stored inmemory units and executed by processors. The memory unit may beimplemented within the processor or external to the processor, in whichcase it can be communicatively coupled to the processor via variousmeans as is known in the art.

For a hardware implementation, the processing units may be implementedwithin one or more application specific integrated circuits (ASICs),digital signal processors (DSPs), digital signal processing devices(DSPDs), programmable logic devices (PLDs), field programmable gatearrays (FPGAs), processors, controllers, micro-controllers,microprocessors, other electronic units designed to perform thefunctions described herein, or a combination thereof.

What has been described above includes examples of one or moreembodiments. It is, of course, not possible to describe everyconceivable combination of components or methodologies for purposes ofdescribing the aforementioned embodiments, but one of ordinary skill inthe art may recognize that many further combinations and permutations ofvarious embodiments are possible. Accordingly, the described embodimentsare intended to embrace all such alternatives, modifications andvariations that fall within the spirit and scope of the appended claims.Furthermore, to the extent that the term “includes” is used in eitherthe detailed description or the claims, such a term is intended to beinclusive in a manner similar to the term “comprising” as “comprising”is interpreted when employed as a transitional word in a claim.

The term “infer” or “inference,” as used herein, refers generally to theprocess of reasoning about or inferring states of a system, environment,and/or user from a set of observations as captured via events and/ordata. Inference can be employed to identify a specific context oraction, or can generate a probability distribution over states, forexample. The inference can be probabilistic, that is, the computation ofa probability distribution over states of interest based on aconsideration of data and events. Inference can also refer to techniquesemployed for composing higher-level events from a set of events and/ordata. Such inference results in the construction of new events oractions from a set of observed events and/or stored event data, whetheror not the events are correlated in close temporal proximity, andwhether the events and data come from one or several event and datasources.

As used in this application, the terms “component,” “module,” “system,”and the like are intended to refer to a computer-related entity, eitherhardware, firmware, a combination of hardware and software, software, orsoftware in execution. For example, a component may be, but is notlimited to being, a process running on a processor, a processor, anobject, an executable thread of execution, a program, and/or a computer.By way of illustration, both an application running on a computingdevice and the computing device can be a component. One or morecomponents can reside within a process and/or thread of execution and acomponent may be localized on one computer and/or distributed betweentwo or more computers. In addition, these components can be executedfrom various computer readable media having various data structuresstored thereon. The components may communicate by way of local and/orremote processes such as in accordance with a signal having one or moredata packets (e.g., data from one component interacting with anothercomponent in a local system, distributed system, and/or across anetwork, such as the Internet, with other systems by way of the signal).

What is claimed is:
 1. An intersection collision prevention systemcomprising: a collision determination unit configured to calculate afirst space between a preceding vehicle running in the same direction asa host vehicle and at least one of a yellow center line and an oncomingvehicle located in the opposite lane with respect to the host vehicleand compare the first space to a predetermined second space to determinea danger of a collision; and a control unit configured to adjust acollision danger warning time point according to a determination resultof the collision determination unit.
 2. The intersection collisionprevention system of claim 1, further comprising at least one of: acamera sensor configured to capture areas around the host vehicle andgenerate image data; and a radar sensor configured to sense the areasaround the host vehicle and generate radar sensing data, wherein thecollision determination unit calculates the first space between thepreceding vehicle and at least one of the oncoming vehicle and theyellow center line on the basis of at least one of the image data andthe radar sensing data.
 3. The intersection collision prevention systemof claim 2, wherein the collision determination unit recognizes at leastone of a lane disconnection and a “go straight”/“turn left” indicationfrom the image data to determine whether the host vehicle enters anintersection.
 4. The intersection collision prevention system of claim3, wherein the collision determination unit virtually generates apredicted route of the host vehicle on the basis of a lane in which thehost vehicle is to run after passing through the intersection, andcalculates the first space on the basis of a space between the predictedroute and at least one of the oncoming vehicle and the yellow centerline and a space between the predicted route and the preceding vehicle.5. The intersection collision prevention system of claim 1, wherein whenthe collision determination unit determines that there is a danger of acollision, the control unit controls a danger warning device so that acollision danger warning time point is put earlier than a referencevalue.
 6. The intersection collision prevention system of claim 1,wherein when the collision determination unit determines that there is adanger of a collision, the control unit controls a braking controldevice so that a deceleration rate is greater than an averagedeceleration rate.
 7. The intersection collision prevention system ofclaim 1, wherein when the collision determination unit determines thatthe first space is greater than the second space, the control unitcontrols a steering control device so that the host vehicle is to passthrough a center of the first space.
 8. The intersection collisionprevention system of claim 1, wherein the collision determination unitdetermines the danger of a collision by using a width of the hostvehicle, a center position in the host vehicle, a width of the oncomingvehicle, a center position in the oncoming vehicle, a width of thepreceding vehicle, and a center position in the preceding vehicle. 9.The intersection collision prevention system of claim 1, wherein thecollision determination unit determines the danger of a collision byusing a width of the host vehicle, a center position in the hostvehicle, the yellow center line, a width of the preceding vehicle, and acenter position in the preceding vehicle.
 10. An intersection collisionprevention method comprising: calculating a first space between apreceding vehicle running in the same direction as a host vehicle and atleast one of a yellow center line and an oncoming vehicle located in theopposite lane with respect to the host vehicle; comparing the firstspace to a predetermined second space to determine a danger of acollision; and adjusting a collision danger warning time point accordingto a collision danger determination result.
 11. The intersectioncollision prevention method of claim 10, further comprising, before thecalculation of a first space, at least one of: capturing areas aroundthe host vehicle and generating image data; and sensing the areas aroundthe host vehicle and generating radar sensing data, wherein thecalculation of a first space comprises calculating the first spacebetween the preceding vehicle and at least one of the oncoming vehicleand the yellow center line on the basis of at least one the image dataand the radar sensing data.
 12. The intersection collision preventionmethod of claim 11, wherein the calculation of a first space comprisesrecognizing at least one of a lane disconnection and a “gostraight”/“turn left” indication from the image data, determiningwhether the host vehicle enters an intersection, and calculating thefirst space when it is determined that the host vehicle enters theintersection.
 13. The intersection collision prevention method of claim12, wherein when the host vehicle enters the intersection, thecalculation of a first space comprises virtually generating a predictedroute of the host vehicle on the basis of a lane in which the hostvehicle is to run after passing through the intersection and calculatingthe first space on the basis of a space between the predicted route andat least one of the oncoming vehicle and the yellow center line and aspace between the predicted route and the preceding vehicle.
 14. Theintersection collision prevention method of claim 10, wherein when thecollision danger determination result is that there is a danger of acollision, the adjustment of a collision danger warning time pointcomprises giving a warning about the danger of a collision so that thecollision danger warning time point is put earlier than a referencevalue.
 15. The intersection collision prevention method of claim 10,further comprising, before or after the adjustment of a collision dangerwarning time point, generating a braking force so that a decelerationrate is greater than an average deceleration rate when the collisiondanger determination result is that there is a danger of a collision.16. The intersection collision prevention method of claim 10, furthercomprising, before or after the adjustment of a collision danger warningtime point, generating a steering force so that the host vehicle is topass through a center of the first space when the collision dangerdetermination result is that the first space is greater than the secondspace.
 17. The intersection collision prevention method of claim 10,wherein the calculation of a first space comprises calculating the firstspace by using a width of the host vehicle, a center position in thehost vehicle, a width of the oncoming vehicle, a center position in theoncoming vehicle, a width of the preceding vehicle, and a centerposition in the preceding vehicle.
 18. The intersection collisionprevention method of claim 10, wherein the calculation of a first spacecomprises calculating the first space by using a width of the hostvehicle, a center position in the host vehicle, the yellow center line,a width of the preceding vehicle, and a center position in the precedingvehicle.